B8 Photosynthesis Flashcards
what do all organisms need
food for respiration
how do plants make their own food
by respiration
how does photosynthesis produce gluocse
by using light
where does photosyntheis take place
in the green parts of plants (especially the leaves)
the cells in algae and plants leaves are full of what
small green parts called chloroplasts
-contain a green substance called chlorophyll
explain the process of photosynthesis
energy is transferred from the environement to the chloroplasts by light
-this energy is then transferred to convert carbon dioxide from the air plus water
what type of reaction is photosynthesis
an endothermic reaction
-also needs an input of energy from the environment
whats the equation for photosynthesis
light
carbon dioxide + water —– glucose + oxygen
for photosynthesis to be successful, what do plants need
-carbon dioxide
-light
-water
state the 5ways plants use glucose for
-for respiration
-making cellulose
-making amino acids
-stored as oils or fats
-stored as fats
what do limiting factors do
affect the rate of photosynthesis
how is the rate of photosynthesis affected
-by the intensity of light
-concentration of CO2
-temperature
explain how the following are limiting factors depending on environmental conditions
-by the intensity of light
-concentration of CO2
-temperature
-at night the light is a limiting factor
-in winter, the temperature
-if its warm and bright enough, the amount of CO2 is limiting
how is chlorophyll a limiting factor of photosynthesis
the amount of chlorophyll in a plant is affected by disease or environmental conditions
state the 3 important graphs for rate of photosynthesis
-not enough light slows down the rate of photosynthesis
-too little carbon dioxide also slows it down
-the temperature has to be just right
state the most common way to artificially create the ideal environment for plants to grow
a greenhouse
-they trap the suns heat and make sure the temperature doesn’t become limiting
-in winter a farmer may use a heater
-in summer it may get too hot so they use shades and ventiliation to cool things down
state what farmers use in a greenhouse
-artificial light, so after the sun goes down to give their plants more quality photosynthesis time
-increase the level of carbon dioxide in the greenhouse, e,g a paraffin heater
-keep plants enclosed, to free them from pests and diseases, also adding fertilisers to the soil
explain how plants are adapted for photosyntheis
-most leaves are broad, giving them a big surface area for light to fall on
-most leaves are thin= diffusion distances for gases is short
-contain chlorophyll in chloroplasts=absorb light
-have veins
-air spaces= allow carbon dioxide to get into the cells and oxygen to leave by diffusion
how do guard cells allow the process of photosynthesis
they have guard cells that open and close the stomata to regulate gas exchange
what is needed for photosyntheis to take place
light
how does algae photosynthesis
as they’re aquatic, they are adapted to photosynthesising in water
-they have a large surface area and absorb carbon dioxide dissolved in water around them
during photosythesis energys transferred
from the environment to the chloroplast by light.
why do plants grow in summer
as they need light, warmth and carbon dioxide which theres more of in summer
name a factor that affects the rate of photosynthesis
light intensity
-more light means more photosynthesis can take place
-if theres little or no light, photosynthesis qill stop
